Dispensing and metering control



v May 24, 1966 T. H. HOULE ETAL DISPENSING AND METERING CONTROL 4Sheets-Sheet 1 Filed July 6, 1964 INVENTOR. H. HOULE A. RUSSELL TiM BYJOHN May 24, 1966' T. H.'HOULE ETAL DISPENSING AND METERING CONTROL 4Sheets-Sheet 2 Filed July 6, 1964 O m m Oh n E. N Q n mm 8 2w u Q? 5INVENTOR. TIM H. HOULE BY JOHN A. RUSSELL y 24, 1956- T. H. HOULE ETAL3, 52,620

DISPENSING AND METERING CONTROL 4 Sheets-Sheet 3 Filed July 6, 1964 WW Vm N A 6 wm W Q on H {\LJE @U M H mm n I\\Nl.- .7 @5 @N 8 w 2 t A r \NINVENTOR TIM H. HOULE JOHN A. RUSSELL BY usdiSTarlqa vndr Attorneys y1966 T. H. HOULE ETAL 3,252,620

DISPENSING AND METERING CONTROL 4 Sheets-Sheet 4 Filed July 6, 1964 xuQEmk 02:05

INVENTOR. H. HOULE JOHN A. RUSSELL BY find! TIM us 21 Star/ e Attornevs5650 6528 $42 m 1 -J. 5?.5352 u 5 2 n a F: n

United States Patent "ice 3,252,620 DlSiENSlNG AND METERING CONTROL TimH. Houle, Wauwatosa, and John A. Russell, Shorewood, Wis, assignors toA. 0. Smith Corporation, Milwaukee, Wis, a corporation of New York FiledJuly 6, 1964, Ser. No. 380,379 12 Claims. (Cl. 222-2) This inventionrelates to an automatic dispensing and metering control system andparticularly to such a control system which is selectively actuated byauthorized personnel through movement of a suitable code device such asa key or the like to permit selective withdrawal of fluid in the absenceof supervisory attendants.

Although the present invention may be employed in general to permitunattended dispensing control, it is of a particular advantage inconnection with bulk storing and loading stations for the distributionof petroleum prod ucts such as gasoline, kerosene, fuel oil and thelike.

In the distribution of petroleum products, bulk loading stations areprovided in which substantial quantities of the several products arestored for subsequent distribution to the retailer. Key and tokenoperated control devices have been suggested such that the bulk loadingstation can be maintained open during a 24 hour period without thenecessity of supervisory attendants at the station at all times. Such asystem provides better utilization of the terminal as well as the trucksthrough a more rapid and around-the-clock loading arrangement. Suchsystems must however provide for a high degree of security, au-

tomatic recording of the amount of product withdrawn and a very reliablesystem such that the danger of breakdown is held to a minimum. Suchsystem must also be arranged and constructed to eliminate explosiveconditions as a result of its operation.

The present invention is particularly directed to a highly reliable andeconomical key or token controlled system which may be mounted directlywithin the area of the dispensing or loading platforms. In accordancewith the present invention, a low voltage control circuit and controlcomponents are mounted within an enclosure within the dispensing areaand interconnected through a low voltage wiring system to controldischarge operation. A plurality of key or like locks are provided onefor each authorized customer. Each of the key lock units takes a uniquekey under the control of the central control station or bulk stationoperator and the respective customers. In accordance with the presentinvention, each of the key actuated locks carries a mercury switchwithin which two sets of contacts are enclosed. The mercury switch is ofa known variety wherein the one set of contacts is housed in one end ofthe unit and the opposite end of the enclosure is contact free such thatwith the free end below the horizontal, the mercury will be held thereinand the contacts will be in an open condition. Reversing the tiltposition such that the contact end is below the horizontal will move themercury mass to the opposite end and thereby complete the circuit acrossthe contacts.

The present mercury switch however further includes a pair of timedcontacts which are closed simultaneously with the initial or firstcontacts. However, in moving to the opposite end, the mercury is heldinto engagement with the extended second or timed contacts such thatthere is a selected time delay in the off direction. The mercury switchis mounted on the key lock unit to dispose the free end below thehorizontal in the standby position. When the key is actuated or moved tothe operated or discharge position, the mercury switch is automaticallytilted to the opposite direction to thereby instantaneously andsimultaneously close the related contacts.

In accordance with the present invention, a pair of Patented May 24,1966 branch circuits is provided for each of the key devices. The onebranch circuit includes a counter mechanism and the second branchcircuit includes the instantaneous contacts in series with a productdischarge relay. Timed contacts are connected in a common circuitconnection between the branch circuits and a power lead tosimultaneously provide power to the two related branch circuits.Additionally, the counter mechanism is operatively connected in circuitthrough an interlocking relay controlled by the transmitter circuit suchthat if for any reason the transmitter contact circuit is not operativethe counter circuit will be opened.

The counting mechanism of this invention may be mounted directly withinthe enclosure and wired through a pulse transmitting circuit of a lowvoltage variety to record the several withdrawals of fluid per customer,Separate circuits are provided for selectively actuating correspondingcounters and the release control relay or the like.

A further very important feature of the present invention provides amechanical interlock between the several key lock units such thatactuation of one unit substantially prevents actuation of the otherunits. The several key lock units are mounted in adjacent relationshipand an interlocking plate member is slidably mounted within theenclosure to span all units having outstanding side slotted members.Interlock levers are interconnected one each to the rotatable portion ofthe key lock units with an outer locking element aligned with and spacedlaterally of a correspondingly positioned locking element in the lockingplate. Thus, the plate may have appropriately spaced slots foraccommodating a lever projection of an aligned lever. The initialrotation of any one of the key lock units will move the locking leverprojection into the related slot and the final rotation of the memberwill cause the lever to move upwardly carrying the locking plate withit. This movement of the locking plate misalign's the other slots andlocking lever projections and thereby positively prevents completemovement of the other key lock units. This provides a very simple andreliable interlocking means which will prevent accidental simultaneousoperation of a plurality of circuits.

Additionally, in accordance with the present invention, a magnetic orother suitable latch assembly is associated with the locking plate. Theinitial key movement moves the locking plate into the locking positionwhich is then releasably held in place by the latch assembly. The latterfeature is of a substantial practical significance to prevent accidentalrelease of the assembly as a result of vibrations, the inherent weightof the assembly and the like.

The present invention thus provides a relatively simple, reliable andeconomical system for an unattended bulk loading plant or the like. Thesystem has a long life and will require a minimum amount of maintenance.Further, the construction with a low voltage circuit arrangement andwith essentially complete elimination against the dangers of arcingpermits its application and direct mounting Within the normallyexplosive vicinity of the bulk loading platform.

The drawings furnished herewith illustrate a preferred construction forcarrying out the present invention and more clearly illustrate theseveral features heretofore discussed as well as other features andadvantages which will be obvious to those familiar with the art.

In the drawings:

FIG. 1 is an elevational diagrammatic view generally illustrating a keystop controlled bulk loading station;

FIG. 2 is an enlarged pictorial view of the control box assemblyconstructed in accordance with the present invention:

FIG. 3 is an enlarged front elevational view with a front panelpartially removed to show certain details of construction;

FIG. 4 is a simplified vertical section through the control unit ofFIGS. 1-3 illustrating the mounting of the several operating componentswithin the enclosure;

FIG. is a vertical section taken on line 55 of FIG. 3 illustrating thecontrol mercury switch mounting system of the present invention;

FIG. 6 is a fragmentary view of the structure shown in FIG. 5illustrating details of a preferred switch construction and the operatedposition of the interlocking mechanism; and

FIG. 7 is a simplified schematic circuit diagram of a control circuitincorporating the compenents shown in FIGS. 1-6, inclusive.

Referring to the drawings and particularly to FIG. 1, a bulk truckloading platform 1 is diagrammatically illustrated and a plurality ofpumping and related operating mechanism, of which only a dischargepiping 2 is shown, is disposed immediately below and otherwise adjacentthe loading station. Generally, a loading nozzle unit 3 is mountedimmediately above the platform area and connected through piping 2 to asource of fuel or suitable petroleum products for loading. A valve unit4 and a meter 5 are connected between the nozzle unit 3 and a bulkstorage tank or other source, not shown, for selective control of thewithdrawal of the product from the bulk storage unit. A petroleumproduct tank truck 6 is shown located to one side of the platform 1 withthe nozzle unit 3 located within the top tank portion of the truck forthe discharge of the petroleum product from the storage unit thereto. Akey actuated control unit 7, particularly forming a part of the presentinvention, is shown mounted at the platform 1 and in accordance with thepresent invention is constructed and connected to control the valve unit4 for controlling the withdrawal of products from the bulk storage unitindependently of any supervisory control or personnel, as hereinafterdiscussed.

Generally, the trucker can enter the loading station and dispose histruck 6 adjacent to the platform 1. By proper actuation of the keyactuated control 7 he can directly withdraw a selected product from thestorage unit without the presence of an attendant. The meter 5 drives apulse transmitter 8 for generating a train of electrical pulsesproportional to the amount of liquid dispensed.

Referring particularly to FIGS. 1 and 2, the control unit 7 includes anenclosure or housing 9 having a plurality of mounting lugs 10 formounting of unit 7 at platform 1. Two columns of key lock units 11 anddummy plug units 12 are secured within an outer side wall of the housing9. The illustrated control 7 is arranged to permit actuation by up toten separate customers; with control connected for six customers throughactuation of corresponding units 11 and dummy plugs 12 provided to closethe opening at which additional customer unit 11 may be subsequentlyprovided by the mere insertion. of proper key lock units. The key lockunits 11 are separately and uniquely actuated by a related key 13, onlyone of which is shown. Additionally, a lamp 14 is mounted immediatelybelow the columns of the key locks 11 to indicate proper operation ofthe control circuit.

Generally, although not specifically shown, an additional switch orother interlocking mechanism, separate from control 7, is provided whichmust be operated after actuation of the key 13 which conditions thedischarge pumping system; for example, a motor-pump unit, not shown, fordischarging of the product. Such additional controls are not essentialto an understanding of the present invention and consequently nodescription or illustration thereof has been given.

In the present invention, the housing 9 is provided with a front openinghaving an outwardly projecting encircling tubular wall 15 defining anouter sealing flange. A front door or cover. 16 having an edge wall 17corresponding to wall 15 is hinged along one edge to the front wall ofthe housing 8. The door 16 telescopes over the wall 15 in the closedposition and is provided with a sealing gasket 18 on its inner face inalignment with the edge of wall 15 to seal the unit against leakage.Apertured lugs 19 are secured to the housing 8 adjacent the wall 15opposite the hinged connection of door 16 and a clamp 20 is releasablysecured thereto as by a bolt unit 21. The door edge Wall 17 is flangedoutwardly and engaged by clamp 20 when the door 16 is closed to tightlyseal the opening to housing 8. An apertured tab 22 on the free edge ofthe door 16 mates with a lug 23 on the housing for locking the door inthe closed position by a suitable lock, not shown.

In accordance with the present invention, an inner door 24 is pivotallysecured or hinged along one edge to the housing 18 in the plane of thefront wall thereof. The door 24 is releasably held in place by a screwtype latch 25 secured to the edge of the door opposite that of thehinged connection. A plurality of counters 26, one for each of the keylock units 11, is mounted within suitable openings within the inner door24 and operatively connected in separate counting circuits by thecorresponding key lock units 11, as subsequently described. In theillustrated embodiment of the invention, each of the counters 26includes a rectangular front mounting panel 27 adapted to overlie theouter edges of the openings for the counter and secured in position byattachment screws 28 extending through aligned openings intocorrespondingly tapped openings in the door 22. The counters 26 extendinto the housing 8 from the door 24. Dummy cover panels 29 are similarlysecured covering the openings corresponding to the position of the dummyplugs 12. This eliminates the expense of providing counters except foroperative positions.

The internal structure of counters 26 may be of any suitableconstruction depending upon the form of signals generated by thedispensing of a product. The present invention has been employed withpulse driven counters operated from a low voltage source of 24 volts. Assuch counters are known and have been employed, no further descriptionthereof is deemed necessary or given.

In the illustrated embodiment of the present invention, a componentsupport chassis or panel 3! is bolted or otherwise secured to the innerback wall of the housing 9 as most clearly shown in FIGS. 3-5. Fourconnecting or terminal strips 31, 32, 33 and 34 are mounted in insulatedrelation generally centrally of the panel 30 to permit simpleinterconnection of the several components as shown in FIG. 7 andpresently discussed. A pulse control module 35 and a pair of capacitors36 and 37 are mounted on the panel to the top and side of the terminalstrips as viewed in FIG. 3. A power transformer 38 is mounted on theupper left-hand corner and provides power to a rectifier bank 39 showngenerally centrally of the unit. A horizontal supporting platform 40 isintegrally formed on the lower end of the panel 30 and projectsforwardly terminating in slightly spaced relation to the inner door 24.A pair of operating relays 41 and 42 is secured to the platform 40 forconnection in circuit through the connecting or terminal strips 31-34.

The panel 30 is supported by a plurality of mounting nut and stud units43 which are welded to and project inwardly from the inner surface ofthe back wall of the housing 9 to completely enclose all of thecomponents within the housing and permit access thereto only through thefront door. Power and signal lead connectors 44 are secured to thebottom wall and locked in place by an internal attachment bolt. Separatelead conduit openings 45 and 46 provide separate connection of the powerand signal leads, not shown. The power connection of the severalcomponents is controlled, in accordance with the present invention, by aplurality of mercury switch units 47, each of which is controlled by oneof the key lock units 11-.

Generally, the key lock units 11 may be of any suitable variety adaptedto receive a unique key 13 and having an internal rotating element; forexample, as shown in US. Patent 2,777,555. Key lock units 11 aretherefore only briefly described. The illustrated unit isdiagrammatically shown as a tumbler type unit having a tumbler 48mounted within an opening in the housing 9 and adapted to receive thekey 13. A stud bolt 49 is threaded into the innermost end of the tumbler43 and provided with a central stop flange 50 abutting the innermost endof the tumbler. A-switch mounting bracket 51 and an interlockingactuating cam 52 are clamped onto the innermost end of the stud bolt 49against the central flange 50 by a clamping hex nut 53 for simultaneousmovement which provides a related actuation of a switch unit 47 andmechanical interlock whereby only one of the key lock units 11 can beactuated at any given time.

The switch mounting bracket 51 is generally an L- shaped member havingan apertured leg secured to the inner end of the stud bolt 49. The otherarm of the bracket 51 extends laterally from the side wall of thehousing to provide a mounting arm upon which the mercury switch unit 47is secured. The switch unit 47 is generally a cylindrical member and anencircling clamp 54 is interconnected to the mounting arm of bracket 51by a suitable attachment nut and bolt unit 55 which passes throughaligned openings in a tab 56 of the clamp 54 and the bracket 51. Asnoted particularly in FIGS. 5 and 6, the inner or adjacent ends of theswitch units 47 of adjacent key lock units 11 overlap. In accordancewith the illustrated embodiment of the invention, the overlap isprovided for by extension of the arms of bracket 51 for the units shownto the right in FIGS. 5 and 6 and by opposite mounting or disposition ofthe clamps 54 with the tabs 56 facing opposite directions. The switchunits 47 are thereby laterally offset with respect to the adjacent sidewall, as most clearly shown in FIG. 3.

Referring particularly to FIG. 6, each of the mercury switch units 47generally includes an encapsulated tubular glass enclosure or housing 57having a set of instantaneous make and break contacts 58 and 59 mountedin one end with a pair of leads 60 secured thereto and extendingoutwardly therefrom. Contact 59 extends longitudinally along the wall ofhousing 57 to the center of the housing and is connected to a centraltime delay contact plate 61 spanning the central portion of the housingand including a small aperture 62 in the lower portion thereof. Acontrol lead 63 extends along the opposite side of housing 47, beginningin spaced relation to plate 61 and having a lead 64 passing outwardlywith leads 60. A mercury mass 65 is provided within housing 57 and isdisposed in accordance with the angular placement of housing 57 withrespect to the horizontal. The mercury 65 passes from the one end as thehousing 57 is tilted to dispose the opposite end below the horizontal.The aperture 62 is selected to allow the free movement of the mercuryfrom the free end to the contact end while restricting the flow of themercury from the contact end or side of plate 61 to the free end of thehousing. In effect, the movement of the mercury switch unit 47 todispose the contact end below the free end provides an essentiallysimultaneous and instantaneous actuation of the two switches formed bythe contacts 61, 63 and common contact 58 which may if desired be formedas a pair of separate contacts. However, when the switch 47 is moved tothe off position, the mercury 65 immediately moves down into engagementwith the plate 61 thus breaking the circuit between the contacts 58 and59 while maintaining a path between the contacts 59 and 63. The mercury65 slowly passes through the opening or aperture 62 in plate 61 andprovides a timed opening of the contacts 59 and 63. Instantaneousclosing of the contacts 59 and 63 and the combined instantaneous openingof contacts 58 and 59 with timed opening of the opposite set of contacts59 and 63 maintains operation of the counter 26 after the valve 5 closesas hereinafter described in more detail with respect to FIG. 7.

Additionally, in accordance with the present invention, a key interlockplate 66 is slidably mounted between the key lock units 11 on the innerwall of the housing 9 and is coupled through cams 52 to restrictoperation of the device to a single key lock unit 11 at any given time.

The illustrated slide interlock plate 66 is generally a U-shaped memberhaving a pair of guide slots 67 and 68 within the base portion thereoffor vertical guided movement as follows. Reference is made to the lowerslot 67 for purposes of description.

A guide bolt 69 passes through the slot 67 and threads into a suitablenut unit 70 welded to the inner side of the housing 9. A guide spacer 71encircles the bolt 69 immediately adjacent the inner wall and includes aguide boss corresponding to the width of and projecting through thecorresponding slot. A washer 72 bears on the guide spacer 71 and incooperation therewith defines an annular guide for the plate.

The U-shaped plate 66 has side arms 73 and 74 which project inwardly inparallel relation immediately adjacent and between the inner portions ofkey lock units 11. Each of the arms is provided with a plurality ofslots 75 and 76, respectively, aligned one each with the respective keylock units 11 as shown most clearly in FIGS. 5 and 6. The slots 75 and76 are spaced somewhat below the corresponding key lock unit 11 forcooperative interaction with a latch arm 77 of the cam 52.

Each of the earns 52 is generally a plate-like member which may beformed of any suitable material; for example, a 12-gauge galvanizedsteel. The cam 52 includes a generally rectangular body with a centralmounting opening which passes over the stud 49 for interconnection withthe corresponding key lock unit 11. The operating arm 77 extendslaterally inwardly from an edge of cam 52 toward the slots 75 or 76. Theoutermost end of the arm 77 generally terminates in lateral alignmentwith the related operating slots 75 and 76 in the standby position; thatis, prior to operation of the key lock unit 11. When a key 13 isinserted into a key lock unit 11, the initial rotation of the key 13effects a corresponding rotation of the stud 49 and the operating arm 77of cam 52 about the axis of the assembly and causes the outermost end ofarm 77 to move into the corresponding slot and into engagement with theupper edge thereof. The final movement of the key 13 to a position whichwill orient the mercury switch unit 47 to locate the mercury mass 65 tothe contact end of housing 57 lifts the interlock plate '66 upwardly tomisalign all of the other slots with respect to the correspondingoperating cam arms and there by positively prevents the final movementof the other key lock units 11, as shown most clearly in FIG. 6. Thus,assuming one of the key lock units 11 has been actuated as justdescribed, the attempted actuation of a second key lock unit 11 willmerely cause slight rotation of the cam 52 until the outer end of thearm 77 engages the adjacent continuous portion of the plate arm 73 or 74which presents a positive stop to further movement thereof.

The interlock plate 66 is biased to the lower, aligned position by acoil spring 78 which is secured to the lower end of the plate 66 througha hook opening 79 and to the bottom wall of the housing by pin or eyehook lug 80. When the operator inserts the key 13, he will have to exerta sufiicient force to overcome the load of the spring 73 to effect aclosing of the mechanism.

The plate 66 is held in a raised position against the action of spring78 by a permanent magnet latch assembly 81 which is secured to the innerwall of the housing 9 by a mounting bracket 82 in upwardly spacedrelation from the top end of the plate 66. A strike plate 83 is weldedor otherwise secured to the top of the slide plate 66. When the plate 66is moved upwardly, by turning of any key lock unit 11, the permanentmagnet latch assembly 81 engages the strike plate 83 and provides apositive magnetic latch of the mechanism in the raised position. Thestrength of the magnet latch assembly 82 is suflicient to overcome theforce of the spring 78 as well as any other minor forces, such asvibration forces which may occur in the vicinity of the assembly.

Thus, the illustrated unit provides a rugged reliable assembly which canbe mounted for operation in the vicinity of the bulk dispensing unit.Generally, the switch units 47 and the counters 26 are interconnected ina control and recording circuit, preferably constructed for example asshown in FIG. 7.

Referring particularly thereto, each of the counters 26 is similarlydiagrammaticlly illustrated as including a drive winding 84 connected todirect current power leads 85 and 86 by the corresponding mercury switchunits 47 and terminal strips. The instantaneous open and break contacts58 and 59 and the timed opening contacts 61-63 as heretofore discussedwith respect to FIG. 6 are shown diagrammatically in FIG. 7 inaccordance with an approved switch illustration. The several connectingstrips 31, 32, and 33 of FIG. 3 are also diagrammatically illustrated inFIG. 7 as pin and socket units with corresponding numbers applied toeach group or bank thereof. In the subsequent description othercorresponding elements in the schematic circuit and the preferredillustrated construction of FIGS. 1-6 are similarly numbered forpurposes of simplicity and clarity of explanation. Further, each of thecounters 26 and mercury switch units 47 are similarly connected inindependent control circuits and consequently a single unit isdescribed. All other units operate in an identical manner, in responseto actuation of an associated lock unit 11, to provide the desired codedcontrol or actuation of the product delivery.

The counter drive winding 84 is connected in a first branch circuit inseries with the switch or contacts 61 and 63 between the one DC. powerlead 85 and a common return lead 87 which is returned to the other DC.power lead 86 via a set of relay contacts 41-1 of relay 41 shown in FIG.4 and connected in the output of pulse control module 35. A resistor 88and a capacitor 89 are connected parallel with the relay contacts toprovide arc suppression in accordance with well known operations.

Each of the counters 26 is a similar device adapted to record a singlecount for each pulsed energization of the counter winding 84. As suchdevices are well known, no further description thereof is given.

The switch contacts 58-59 of the mercury switch unit 47 are connected ina product release branch circuit having one end connected at a junction90 between the winding 84 and the related switch contact 61 which iscommon to contact 59. The opposite contact 58 is connected to a commonreturn lead 91 through one of the connecting strips 32. A groundinterlock contact unit 92 and a product release relay 42, also shown inFIG. 4, are connected in series between lead 91 and power lead 86. Theground interlock contact unit 92 must be connected to and ground thetruck 1, in accordance with well known circuit connection, prior toenergization of the relay 42 for releasing of the products.

The relay 42 controls first and second sets of contacts 42-1 and 42-2connected in separate power circuits for controlling a pair of controldevices 93 for a given product to be selectively delivered to the truck.For example, in a bulk loading plant, a start motor control device and ablock valve control device might be actuated by the closure of contacts42-1 and 42-2.

The operation of the illustrated embodiment of the invention is brieflysummarized as follows. Generally, the key lock control unit 7 has thefront door 16 closed and locked in place to prevent unauthorizedtampering of the components within the enclosure or housing 8. When aproduct is to be withdrawn, the driver properly positions his truck 6and interconnects the ground interlock 'unit 92 to the truck to providea circuit between the common lead 91 and the product release relay 42shown in FIG. 7. The key 13 is inserted into the appropriate key lockunit 11 and rotated. As shown in FIGS. 5 and 6, the initial rotation ofthe key 13 rotates cam 52 to pivot arm 77 into the aligned slot or 76and into engagement with the upper edge thereof. Simultaneously, thecorresponding mercury switch unit 47 is pivoted but remains tiltedgenerally in the off position such that the contacts remain open. Thefinal movement of the key 13 causes essentially simultaneous closure ofthe contacts 58-59 and 61-63 and the raising of the interlock plate 66.As a result, once the operator has turned the key 13 to an operativeposition, he must return it to the off position before another key lockunit 11 can be actuated.

The magnetic latch assembly 81 positively holds the key 13 and theassociated mechanism in the actuated position until the operatorprovides a positive return force,

The closing of contacts 58-59 and 61-63 completes the circuit to theproper counter winding 84 and to the product release relay 42. The truckdriver may then have to actuate an auxiliary control, not shown, todeliver the product to the truck.

To terminate delivery, he may operate the auxiliary control and thenturn the key 13 to the oil position, or he may merely turn the key tothe ofi position. The latter instantaneously opens the branch circuit tothe product release relay 42 as a result of the opening of the contacts58-59. As a result, the circuit actuation of product delivery isdisabled and the positive delivery of fluid is immediately terminated.

However, the contacts 61-63 remain closed for the time period requiredfor mercury 65 to pass through opening 62 sufficient to break thecircuit there'between. This then maintains power to the counter drivewinding 84 for a short period. This is desirable to maintain theoperative circuit connection to the counter 26 for recording any finalflow of fluid through the metering unit. This unit is normallydownstream from the drive unit and the pump and valve unit and thus ifthe timed opening of the contacts 61-63 was not provided and the counter26 were instantaneously disconnected, a small but noticeable quantity ofthe product would be discharged without recording thereof. Although theamount in any given delivery may be relatively small, the accumulativeamount would be appreciable and undesirable. Use of the present dualswitching arrangements provides a very simple and inexpensive means forautomatically eliminating such loss The time required to record thisfinal How is so minute that there is essentially no danger that therewill be an accidental closing of another circuit prior to the opening ofthis circuit and the simultaneous recording on two counters of the finalflow of fluid. Therefore, although such an accidental occurrence orrecording is possible, the probability thereof is so slight as to benegligible and of no practical significance.

Periodically, the attendant of the bulk loading plant will take areading of the respective counters for billing purposes and the like.

Further, if at any time it is desired to withdraw credit from a keyedcustomer, this may be rapidly and efiiciently done by the simpleopeningof the inner door and the removal of the appropriate lead shownat the circuit strip connector which connects the positive power lead 85to the corresponding circuit for the related counter 26.

The present invention thus provides a relatively simple and economicallow voltage control system which can be mounted in a bulk loading plantto provide for unattended dispensing of the several stored products. Theencapsulated enclosure of the mercury switch unit 47 and the low voltagecircuits within the platform area elimwithout violation of underwritinglaboratory rules and the like. The mechanical interlock of the key lockunits 11 provides a reliable means for restricting operation of thesystem to a single customer at any given time without undulycomplicating the control mechanism,

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

We claim:

1. An unattended dispensing system for controlling actuation of meansfor feed of flowable material, comprising a control circuit for saidmeans having a plurality of separate branch circuits, one for eachcustomer and each of which is operable to energize the means,

a plurality of counters, one for each customer,

switch means connected in said control circuit to selectively completethe branch circuits,

counter switch means connected to selectively operably connect saidcounters to record the material flow,

a plurality of coded input elements having a first position to turn offrelated switch means and a second position to turn on the correspondingswitch means,

timed holding means to maintain the counter switch means closed for aselected period after the corresponding input element is moved irom thesecond to the first position, and

an interlock means actuated by each of said input elements and arrangedto prevent actuation of more than one element at one time.

2. An unattended dispensing system for controlling actuation ofdispensing means for a fiowable material, comprising a control circuitfor said dispensing means having a plurality of separate branchcircuits, one for each customer and each of which is operable toenergize the dispensing means,

a plurality of counters, one for each customer,

switch means connected in said control circuit to selectively completethe branch circuits,

switch means connected to selectively operably connect said counters torecord the material flow,

a plurality of coded input units adapted to be actuated to actuate therelated switch means, and

a mechanical interlock means coupled to be actuated by each of saidinput units and arranged to limit actuation to one unit at a time.

3. The unattended dispensing system of claim 2 wherein said interlockmeans includes a plurality of operators secured one each to the inputunits and similarly positioned thereby between a standby position and anoperable position and interlocking plate element selectively coupled toeach operator by an aligned slot and arm coupling in the standbyposition of all input units, movement of any input unit effectingengagement of the corresponding coupling and destroying alignment of allother couplings.

4. The unattended dispensing system of claim 2 wherein,

said input units are key actuated lock units having a rotatable innermember supporting the related switch means for operation and a movablelocking member is secured to the inner member, and

the interlocking means includes a slidably mounted U- shaped platehaving side walls with slots aligned with and disposed in the path ofthe locking members whereby initial rotation of any lock unit moves thecorresponding member into the slot and final rotation thereof moves theplate to misalign all other slots and locking members.

5. An unattended fluid dispensing and indicating unit for a petroleumproduct bulk loading station,

a circuit having a plurality of control branches and indicating branchesconnected to power supply lines with related control branches andindicating branches connected through a separate common circuit portion,

a plurality of control switches, one for each customer and each havingan instaneous make and break contact means connected in said controlbranches and a timed break contact means connected in said indicatingbranches,

a control housing for said circuit and said control' switches,

a plurality of input devices one for each of said control switchesmounted in the wall of the housing and having each constructed toreceive a unique cooperative actuator for operating a movable memberwithin the housing,

means coupling said movable members to the corresponding switches, and

an interlocking element disposed to be engaged 'by each movable memberand moved thereby to prevent movement of any other movable member.

6. The unattended fluid dispensing and indicating unit of claim 5 havingat least one terminal strip in the control branches whereby an inputdevice is made inoperable by removal of a single lead from the terminalstrip.

7. The dispensing and indicating unit of claim 5 wherein,

said input devices are key actuated lock units having a rotatable innermember and said movable members are secured to rotate with the innermember with a locking leg extending generally radially therefrom, and

said interlocking element is a slidably mounted U- shaped plate havingside walls with slots aligned with and disposed in the path of thelocking legs whereby initial rotation of any lock unit moves thecorresponding leg into the slot and engagement with the edge thereof andfinal rotation thereof moves the plate to misalign all other slots andlegs.

8. The dispensing and indicating unit of claim 6 wherein,

each of said switches is a mercury switch having a hermetic enclosurewith the instantaneous make and break contact means in a contact end andthe timed break contacts in the corresponding end and the centralportion and a mercury mass held at and between the opposite ends inaccordance with the angular positioning of the enclosure, and

means to mount said mercury switch upon said rotatable inner member andarranged to dispose the free end of the enclosure below the horizontalin the standby position and to dispose the contact end below thehorizontal during the final rotation of the corresponding lock unit.

9. An unattended fluid dispensing and indicating systern for a petroleumproduct bulk loading station,

a low voltage circuit having a plurality of control branches and relatedindicating branches connected to power supply lines with each relatedcontrol branch and indicating branch connected to one power line througha separate common circuit portion,

a plurality of hermetically enclosed control switches,

one for each customer and each having an instantaneous make and breakcontact means connected in said control branch and a timed break contactmeans connected in said common circuit portion,

a control housing for said low voltage circuit and said controlswitches,

a plurality of input devices one for each of said control switchesmounted in the wall of the housing and having each constructed toreceive a unique cooperative actuator for operating a movable memberwithin the housing,

means mounting the corresponding switches upon said movable members foractuation in accordance with the movable member, and

an interlocking element disposed to be engaged by each movable memberand moved thereby to prevent movement of any other movable member.

10. An unattended fluid dispensing and indicating system for a petroleumproduct bulk loading station, comprising a control housing adapted to bemounted in the flow and dispensing area of the station,

a control circuit mounted within the housing and including a pluralityof paralleled dispensing control branches and a similar plurality ofrelated indicating branches,

a control relay connected in series with one end of the controlbranches,

a pulse means connected in series with one end of the indicatingbranches,-

means to actuate the pulse means in accordance with the flow,

a similar plurality of electrically pulse operated counters connectedone each in each indicating branch,

a similar plurality of mercury control switches one for each of therelated control and indicating branches and each of which includes a setof instantaneous make and break contacts and a set of timed breakcontacts within a hermetic enclosure, said instantaneous contacts beingconnected in said control branches and said timed break contacts beingconnected in common -to the related control and indicating branches,

a set of low voltage power leads in the housing and connected to theparalleled branches through said switches and said pulse means toselectively energize the control relay and said counters,

a control housing for mounting directly in the flow and dispensing area,

a plurality of input devices one for each of said control switchesmounted in the Wall of the housing and having each constructed toreceive a unique cooperative actuator for operating a movable memberwithin the housing,

means coupling said movable members to the corresponding switches, and

an interlocking element disposed to be engaged by each movable memberand moved thereby to prevent movement of any other movable member.

11. The fluid dispensing and indicating system of claim 10 wherein,

said input devices are key actuated lock units having a rotatable innermember and said movable mem-.

actuation of dispensing means for feed of flowable material, comprisinga plurality of indicating means,

a control circuit for said dispensing means and said indicating means,

a plurality of control switches, one for each indicating means, each ofsaid switches including a hermetic tu'bular enclosure with a set ofinstantaneous contacts in a contact end thereof and a set of time delaycontacts in the central portion and the contact end thereof forengagementby a mass within the enclosure and movable between the contactend and a contact free end, said instantaneous contacts being connectedfor actuating the dispensinglmeans and the time delay contacts actuatingthe cormsponding indicating means,

a plurality of code input means, one for each of the control switches,

means to mount said switches for positioning by the related input meansand arranged to dispose the free end of the enclosure below thehorizontal in the standby position and to dispose the contact end belowthe horizontal during the vfinal movement of the corresponding inputmeans, and

an interlock means actuated by said input means and arranged to preventactuation of more than selected means at one time.

References Cited by the Examiner UNITED STATES PATENTS 1,204,241 11/1916Bradley 194-5 2,712,885 7/1955 Winship 22226 3,038,638 6/1962 Notter22226 LOUIS J. DEMBO, Primary Examiner.

CHARLES R. CARTER, Examiner.

1. AN UNATTENDED DISPENSING SYSTEM FOR CONTROLLING ACTUATION OF MEANSFOR FEED OF FLOWABLE MATERIAL, COMPRISING A CONTROL CIRCUIT FOR SAIDMEANS HAVING A PLURALITY OF SEPARATE BRANCH CIRCUITS, ONE FOR EACHCUSTOMER AND EACH OF WHICH IS OPERABLE TO ENERGIZE THE MEANS, APLURALITY OF COUNTERS, ONE FOR EACH CUSTOMER, SWITCH MEANS CONNECTED INSAID CONTROL CIRCUIT TO SELECTIVELY COMPLETE THE BRANCH CIRCUITS,COUNTER SWITCH MEANS CONNECTED TO SELECTIVELY OPERABLY CONNECT SAIDCOUNTERS TO RECORD THE MATERIAL FLOW, A PLURALITY OF CODED INPUTELEMENTS HAVING A FIRST POSITION TO TURN OFF RELATED SWITCH MEANS AND ASEC-